In the key and lock art, the usual practice is to first manufacture the keys, after which the code of each key, for example the notches formed along the edge of the key, are read, the results of that reading then being used to manufacture the corresponding lock cylinder, or specifically, to determine the characteristics of the tumbler pins thereof so that the lock cylinder mates with its respective key.
One known key reading technique is shown in my prior U.S. Pat. No. 3,264,742. In the device shown therein, a separate contact pin associated with each key notch position mechanically operates a resistor arm to create an electric signal dependent upon the depth of that particular notch. However, while this prior device is operable for its intended purpose, it is relatively slow and therefore not acceptable for use with more modern high speed key and lock manufacturing techniques.
Thus, a need exists for a new and improved method and apparatus for reading the code of a key, for example the notches in the edge of a key, especially in connection with the manufacture of a corresponding, mating lock cylinder.